Hello to all the mailing list. I'm playing around with my X310, as far as I can understand the maximum ethernet frame size supported by this device is 8000. (in fact in x300_impl.hpp there is this constant static const size_t X300_10GE_DATA_FRAME_MAX_SIZE = 8000;).
Because I'm curious I made an attempt and modified this value to 9710 (the maximum MTU size for my linux box) and I put some cout inside the function determine_max_frame_size (in x300_impl.cpp). This function seems to negotiate the MTU between the X310 and the host. What I observerd is that if I keep X300_10GE_DATA_FRAME_MAX_SIZE=8000 determine_max_frame_size negotiate the rigth MTU recv_test_frame_size = 6004 recv_size = 6004 recv_test_frame_size = 7004 recv_size = 7004 recv_test_frame_size = 7504 recv_size = 7504 recv_test_frame_size = 7752 recv_size = 7752 recv_test_frame_size = 7876 recv_size = 7876 recv_test_frame_size = 7940 recv_size = 7940 recv_test_frame_size = 7972 recv_size = 7972 recv_test_frame_size = 7988 recv_size = 7988 recv_test_frame_size = 7996 recv_size = 7996 recv_test_frame_size = 8000 recv_size = 8000 while if I set X300_10GE_DATA_FRAME_MAX_SIZE=9710 when determine_max_frame_size try to send more than 8912 bytes, happens like a brick on the X310, no more ethernet traffic is possible (even ICMP). This sounds really like somewhere there is a buffer of 8192 bytes in length. I made also an attempt to modify the MTU parameter on the noc_shell and axi_wrapper modules without results. Now I perfectly understand that I want to use the device, let me say, out of specification, but I want to ask if there is way to have a MTU larger than 8000. Thank you in advance for your attention. Best
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